How Do Access Specifiers (Public, Protected, Private) Affect Class Member Accessibility and Inheritance?

What are Access Specifiers?

Access specifiers, namely public, protected, and private, define the accessibility of class members, influencing how other classes can access them.

• Public: Members are accessible from anywhere.
• Protected: Members are accessible within the class and derived classes, but not by other classes.
• Private: Members are accessible only within the class.

Inheritance and Access Specifiers

Inheritance involves the creation of a new class, called the derived class, which inherits properties from an existing class, called the base class. The access specifiers determine how derived classes can access base class members:

• Public Inheritance: Public base class members become public members of the derived class. Protected members become protected.
• Private Inheritance: Public base class members become private members of the derived class. Protected members also become private.
• Protected Inheritance: Public base class members become protected members of the derived class. Protected members also become protected.

Usage Considerations

Public Inheritance:

• Provides maximum accessibility, but can lead to tight coupling.
• If you want derived classes to have unrestricted access to base class members, use public inheritance.

Private Inheritance:

• Provides least accessibility, limiting access to derived class members only.
• Use private inheritance when you want to hide implementation details from derived classes or prevent modification of inherited data.

Protected Inheritance:

• Offers a balance between private and public inheritance.
• Allows derived classes to access protected members, enabling extension but also restricting indiscriminate access.

Important Notes:

• Access specification applies to classes, not to objects.
• A derived class can only access members of its own base class.
• Friends can access members regardless of access specifiers.

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